Algebraic structures | Semigroup theory

Semigroup with two elements

In mathematics, a semigroup with two elements is a semigroup for which the cardinality of the underlying set is two. There are exactly five distinct nonisomorphic semigroups having two elements: * O2, the null semigroup of order two, * LO2 and RO2, the left zero semigroup of order two and right zero semigroup of order two, respectively, * ({0,1}, ∧) (where "∧" is the logical connective "and"), or equivalently the set {0,1} under multiplication: the only semilattice with two elements and the only non-null semigroup with zero of order two, also a monoid, and ultimately the two-element Boolean algebra, * (Z2, +2) (where Z2 = {0,1} and "+2" is "addition modulo 2"), or equivalently ({0,1}, ⊕) (where "⊕" is the logical connective "xor"), or equivalently the set {−1,1} under multiplication: the only group of order two. The semigroups LO2 and RO2 are antiisomorphic. O2, ({0,1}, ∧) and (Z2, +2) are commutative, and LO2 and RO2 are noncommutative. LO2, RO2 and ({0,1}, ∧) are bands and also inverse semigroups. (Wikipedia).

Video thumbnail

Inner & Outer Semidirect Products Derivation - Group Theory

Semidirect products are a very important tool for studying groups because they allow us to break a group into smaller components using normal subgroups and complements! Here we describe a derivation for the idea of semidirect products and an explanation of how the map into the automorphism

From playlist Group Theory

Video thumbnail

Group theory 7: Semidirect products

This is lecture 7 of an online course on group theory. It covers semidirect products and uses them to classify groups of order 6.

From playlist Group theory

Video thumbnail

GT14. Semidirect Products

EDIT: At 6:24, the product should be "(e sub H, e sub N)", not "(e sub H, e sub G)" Abstract Algebra: Using automorphisms, we define the semidirect product of two groups. We prove the group property and construct various examples, including the dihedral groups. As an application, we

From playlist Abstract Algebra

Video thumbnail

Inner Semidirect Product Example: Dihedral Group

Semidirect products explanation: https://youtu.be/Pat5Qsmrdaw Semidirect products are very useful in group theory. To understand why, it's helpful to see an example. Here we show how to write the dihedral group D_2n as a semidirect product, and how we can describe that purely using cyclic

From playlist Group Theory

Video thumbnail

Groups in abstract algebra examples

In this tutorial I discuss two more examples of groups. The first contains four elements and they are the four fourth roots of 1. The second contains only three elements and they are the three cube roots of 1. Under the binary operation of multiplication, these sets are in fact groups.

From playlist Abstract algebra

Video thumbnail

Walter van Suijlekom: Semigroup of inner perturbations in Non Commutative Geometry

Starting with an algebra, we define a semigroup which extends the group of invertible elements in that algebra. As we will explain, this semigroup describes inner perturbations of noncommutative manifolds, and has applications to gauge theories in physics. We will present some elementary e

From playlist HIM Lectures: Trimester Program "Non-commutative Geometry and its Applications"

Video thumbnail

GT2. Definition of Subgroup

Abstract Algebra: We define the notion of a subgroup and provide various examples. We also consider cyclic subgroups and subgroups generated by subsets in a given group G. Example include A4 and D8. U.Reddit course materials available at http://ureddit.com/class/23794/intro-to-group-

From playlist Abstract Algebra

Video thumbnail

Definition of a group Lesson 24

In this video we take our first look at the definition of a group. It is basically a set of elements and the operation defined on them. If this set of elements and the operation defined on them obey the properties of closure and associativity, and if one of the elements is the identity el

From playlist Abstract algebra

Video thumbnail

AlgTopReview4: Free abelian groups and non-commutative groups

Free abelian groups play an important role in algebraic topology. These are groups modelled on the additive group of integers Z, and their theory is analogous to the theory of vector spaces. We state the Fundamental Theorem of Finitely Generated Commutative Groups, which says that any such

From playlist Algebraic Topology

Video thumbnail

"New Paradigms in Invariant Theory" - Roger Howe, Yale University [2011]

HKUST Institute for Advanced Study Distinguished Lecture New Paradigms in Invariant Theory Speaker: Prof Roger Howe, Yale University Date: 13/6/2011 Video taken from: http://video.ust.hk/Watch.aspx?Video=6A41D5F6B1A790DC

From playlist Mathematics

Video thumbnail

On the structure of quantum Markov semigroups - F. Fagnola - PRACQSYS 2018 - CEB T2 2018

Franco Fagnola (Department of Mathematics, Politecnico di Milano, Italy) / 06.07.2018 On the structure of quantum Markov semigroups We discuss the relationships between the decoherence-free subalgebra and the structure of the fixed point subalgebra of a quantum Markov semigroup on B(h) w

From playlist 2018 - T2 - Measurement and Control of Quantum Systems: Theory and Experiments

Video thumbnail

Markus Haase : Operators in ergodic theory - Lecture 3 : Compact semigroups and splitting theorems

Abstract : The titles of the of the individual lectures are: 1. Operators dynamics versus base space dynamics 2. Dilations and joinings 3. Compact semigroups and splitting theorems Recording during the thematic meeting : "Probabilistic Aspects of Multiple Ergodic Averages " the December 8

From playlist Dynamical Systems and Ordinary Differential Equations

Video thumbnail

BAG1.4. Toric Varieties 4 - Spec(R) and Affine Semigroups

Basic Algebraic Geometry: In this part, we introduce Spec(R) and affine semigroups. This allows us to give yet another characterization of affine toric varieties in terms of affine semigroups.

From playlist Basic Algebraic Geometry

Video thumbnail

Type Classes for Mathematical Formalizations in Coq - Matthieu Sozeau

Matthieu Sozeau INRIA Paris; Member, School of Mathematics October 3, 2012 For more videos, visit http://video.ias.edu

From playlist Mathematics

Video thumbnail

The potential of AI, illustrated in the classification of finite..(Lecture 5) by Carlos Simpson

INFOSYS-ICTS RAMANUJAN LECTURES EXPLORING MODULI SPEAKER: Carlos Simpson (Université Nice-Sophia Antipolis, France) DATE: 10 February 2020 to 14 February 2020 VENUE: Madhava Lecture Hall, ICTS Campus Lecture 1: Exploring Moduli: basic constructions and examples 4 PM, 10 February 2020

From playlist Infosys-ICTS Ramanujan Lectures

Video thumbnail

Zero dimensional valuations on equicharacteristic (...) - B. Teissier - Workshop 2 - CEB T1 2018

Bernard Teissier (IMJ-PRG) / 06.03.2018 Zero dimensional valuations on equicharacteristic noetherian local domains. A study of those valuations based, in the case where the domain is complete, on the relations between the elements of a minimal system of generators of the value semigroup o

From playlist 2018 - T1 - Model Theory, Combinatorics and Valued fields

Video thumbnail

Introduction to Number Theory

Cryptography and Network Security by Prof. D. Mukhopadhyay, Department of Computer Science and Engineering, IIT Kharagpur. For more details on NPTEL visit http://nptel.iitm.ac.in

From playlist Computer - Cryptography and Network Security

Video thumbnail

Semigroups and Abelian Algebraic Structures

Thesis: https://www.researchgate.net/publication/328163392_The_Cayley_type_theorem_for_semigroups Merch :v - https://teespring.com/de/stores/papaflammy Help me create more free content! =) https://www.patreon.com/mathable Paper's Playlist: https://www.youtube.com/watch?v=nvYqkhZFzyY&lis

From playlist Bachelor's Paper

Video thumbnail

Product group example

There is no better way of understanding product groups than working through and example. In this video we look at the product group of the cyclic group with two elements and itself. The final result is isomorphic to what we call the Klein 4 group.

From playlist Abstract algebra

Video thumbnail

From Magmas to Fields: a trippy excursion through algebra - SoME2 3b1b

A gentle introduction to the most basic definitions in Algebra (and how to make them stick forever). If you always struggled to remember what a field is this video is for you. You will learn about: 0:00 This videos aim 1:20 Sets 1:52 Magmas 3:15 Semigroups 4:39 Monoids 5:22 Groups 6:04 Co

From playlist Summer of Math Exposition 2 videos

Related pages

Truth value | Semilattice | Complemented lattice | Empty semigroup | Lattice (order) | Exclusive or | Group (mathematics) | False (logic) | Two-element Boolean algebra | Null semigroup | Symmetric group | Band (algebra) | Semigroup | Distributive lattice | Trivial semigroup | Semigroup with three elements | On-Line Encyclopedia of Integer Sequences | Mathematics | Special classes of semigroups | Inverse semigroup | Cyclic group | Logical connective | Matrix multiplication | Logical conjunction | Cardinality | Matrix (mathematics) | Binary operation | Cayley table | Monoid